Heat treatment influence on HV^^ hardness of
welded joints in offshore constructions
H. Bugiacki
Faculty of Ocean Engineering & Ship Technology
Technical University of Gdansk, Poland
Abstract
The work presents the results of measurements of Hl'max hardness of butt welded
joints for thermally improved 18G2A and 18G2AV steel plates before and after heat
treatment 580°C/1 hour/25mm of joint thickness with cooling in air.
1 Introduction
For offshore constructions plates are used that are either quenched and tempered or
obtained as a result of thermo-mechanically controlled rolling process, with the end
of rolling temperature below that of austcnite rccrystallization [1-3]. At the same
time the rules of classification societies and norms [2,4] for offshore constructions
require heat treatment after welding 600_+20"C/1 hour/25mm of thickness with
cooling in air of plates g=50mm thick, placed in the area of water spindrift, and
joints gf=63mm thick in the underwater part of offshore